STEM32 Lesson Plan Template
Teacher’s Name: Nancy Azcona
School: MS 88
STEM32 PD Attended: STEM Training with Wildlife Conservation Society (WCS)
Lesson Title
Hatching Brine Shrimp
Grade Level
NYS Standards
6 to 8
5.1a
Animals and plants have a great variety of body plans and internal
structures that contribute to their ability to maintain a balanced condition.
5.1b An organism’s overall body plan and its environment determine the
way that the organism carries out the life processes.
Objective(s)
Students will develop an understanding of how the growth and survival of an
organism (brine shrimp) depends on physical conditions.
Students will design an experiment to determine the optimum salinity of
water needed to hatch brine shrimp.
Materials and
Websites
Smart Start
Mini-Lesson
Application
(Group Work)
Magnifying glasses
Containers in which to hatch brine shrimp (e.g., plastic 16-20 ounce water or
soda bottles, from which the labels can be peeled so students can see inside
the bottles, and the brine shrimp can get light)
Spring water or aged tap water
Rock or sea salt
Growlite bulb—strong illumination is necessary for hatching; a standard
growlite bulb, available in an aquarium supply store, should be sufficient
Brine shrimp—these can be obtained from many pet or aquarium
Provide students with a nature video or picture book to describe saltwater
wetlands. Discuss the characteristics of saltwater wetlands.
Animals that live in salt marshes, mangrove swamps, and tidal flats all have
built-in adaptations to deal with saltwater and changing levels of salinity.
For example, brine shrimp can survive in seawater and brackish water and
can be found in salt lakes and brine ponds all over the world. However,
brine shrimp have no defense against predation, so can best thrive in
conditions in which their predators cannot, such as high salinity and
temperature.
1. Place some brine shrimp eggs on a large piece of paper and have students
view the eggs through a magnifying glass and describe what they see. What
do they think they are seeing?
2. Tell students that they are looking at the eggs of an organism that lives in
saltwater lakes and, like the animals that live in saltwater wetlands, is
adapted to salty conditions. Explain that the eggs they are looking at can be
hatched in saltwater, and that they will design an experiment to figure out
just how salty the water should be in order to hatch the most eggs.
3. Ask students to brainstorm about ways in which they can determine the
optimum level of salt in the water for hatching (i.e., the level of salt that
allows the most eggs to hatch).
4. Next, have students work in groups to design an experiment to determine
this optimum level of salinity for hatching. For example, students could set up
several containers of water, putting freshwater in one and water that's
increasingly salty in the others.
5. Have students answer the following questions:
a) In this experiment, what is the dependent variable? (It is the
number of eggs to hatch.)
b) What is the independent variable? (Salinity.)
c) How many different salinities will you test?
d) What other variables will you keep constant? (Temperature, the
number of eggs, etc.)
e) How will you keep those variables constant?
6. Now have students carry out their experiments. Students should use only
spring water or aged tap water in the mixtures, as brine shrimp are sensitive
to poor water quality. In addition, instruct students to label all containers
with the ratio of salt (rock salt) to water used. After the containers have been
filled with salty water and labeled, have students add some eggs to each
container and observe what happens (it will take a day or two for the eggs to
hatch). Remember that strong illumination is necessary for hatching.
Conclusion
FYI: One tablespoon [15 ml] of salt mixed with one cup [240 ml] of water is
usually a good mixture for hatching the brine shrimp eggs.
Once students have completed their experiments, have them present their
results to the class, highlighting what they found to be the optimum salinity
for hatching (i.e., the salinity that allowed the most eggs to hatch).
Students should display summaries of their experiments and conclusions on
poster boards and accompany these with written reports. They should
include tables or graphs to show the hatching rate for the various ratios of
salt to water tested. Power Point presentations, Excel graphs, etc. can be
used to enhance these reports.
Extensions:
In addition, have students provide written responses to the question: "How
could this have been a better experiment?" You should expect students to
note things such as better control of variables and more precise equipment,
for example.